Kinetics experiments were performed with several different sizes of spherical catalyst pellets. In all experiments, the bulk

concentration of A was fixed at $0\mathrm{.}025mo\frac{l}{L},$ with A fed through the catalyst bed at $350C.$ The reaction is suspected to be first

order, of the form $A$ products. Data are shown in the table, below:

a$)$ Determine the rate constant for the intrinsic reaction and the effective diffusivity based on the $1mm$ and $20mm$ particles. State all

assumptions.

b$)$ Determine the effectiveness factor and Thiele modulus for each particle.